Underreamer



E. C. AND W. W. WILSON.

UNDERREAMER.

APPLICATION FILED MAYZI, I9I5.

Patented Apr. 27, 1920.

'I'EI mi. t

5 1. di #l 1H R ATTQRNEY UNITED STATES PATENT OFFICE.

ELIH'U' C. WILSON AND WILLIAM W. WILSON, 0F LOS ANGELES, CALIFORNIA,

ASSIGNORS TO SAID WILLIAM W. WILSON.

'UNDERREAMER.

Application led May 21, 1915.

To all whom t may concern:

Be it knownk that we, ELIHU C. WILSON and WiLLiAivrW. WILSON, both citizens of the United States, residing at Los Angeles, in the county of Los Angeles and State of California, have jointly invented new and useful Improvements in Underreamers, of which the following is a specification.

This invention relates to underreamers for enlarging oil'well holes to permit the lowering of the casing therein, the uses and functions of such mechanism and devices being well understood in the art of oil well drilling or boring. Such underreamers as employed in generally adopted practice comprise bits or cutters, a body in connection with which such bits or cutters are assembled, and means carried by the body for moving the bits or cutters into expanded or working positions, which results are produced by the cooperation of the cutters, in movement, with portions of the body or means upon or carried by the same. The means for moving the cutters are preferably organized to operate automatically to cause expansion of the cutters when they have been lowered beneath the casing. cutters is produced voluntarily before introduction of the underreamer into the casing, prior to lowering the same, and is produced automatically upon withdrawal of the cutters into'the'casing from their working positions in the hole beneath the same.

The means fory automatically expanding the cutters into working positions preferably include a tension or compression member or coil spring acting upon a rod movably mounted in the body and upon which the cutters are suspended. This spring is confined at one end by the rod, and must be confined at the other end by means connected with the body, to produce the proper compression or tension. Such latter means must be withdrawn to permit the rod and spring to be removed, and permit the disassembling of the reamer or the removal of the cutters for sharpening or replacement. This removing action must Ybe simple, as itfis required repeatedly to remove and sharpen or replace the cutters during drilling operation. Likewise, such means for confining one end of the spring must be simple in manipulation to permit assembling or re-assembling of the rod, spring and cutters in connection with the body-all to the end that delay and Specification of Letters Patent.

The collapsion of the Serial No. 29,482.

inconvenience may be obviated in the handling and use of the reamer.

In a prior application for U. S. atent for underreamers, filed by Elihu C. ilson 0f March 18th, 1913, Serial No. 755,170, there is disclosed a key for the purpose of conining the lower end of this spring of the `cutter-mounting, carrying and actuating Acutters and their carrying rod and the broken spring to be lost in the hole. The present invention provides an improvement in underreamers directed particularly at the nature of such spring-holding means. We now provide a key of unitary or one-piece form, which fits snugly within the body of the reamer, instead of loosely, and which is positively held in position therein independently of the pressure of the spring; means being provided, one of which is fixed and the other removable, for preventing inadvertent displacement of the key in either direction. It results from the employment of this key that the derangement of the spring or any of the working parts of the reamer will not affect its positive retention in working position, until it is-voluntarily removed, the accidental loss of the cutters and suspending parts in the hole being rendered impossible due to any failure of such key to act and retain its working position.

In addition to the general objects and purposes above set forth, the invention has as further objects the provision of an improved reamer which will be generally superior, as to the attributes of the invention,

with respect to simplicity and inexpensiveness of construction and organization, posi- Vtiveness in operation and action, Vconvenience in use and manipulationv and assembling and disassembling, and compactness in form, and which will be generally superior in efiiciency and serviceability.

The invention consists in the novel and Patented Apr. 27, 1920. l

useful provision, formation, application, construction, combination, association and interrelation of parts, members and features, all as hereinafter described, shown in the drawing and finally pointed out in claims.

ln the drawing:

Figure 1 is a central vertical sectional view of an improved underreamer construeted in accordance with the invention, the same being partly broken away and partly in elevation, and likewise being shown in position adjacent to the shoe or lower end of the oil well casing in position in an oil well hole, the cutters or bits being in re tracted positions;

Fig. 2 is a view similar to Fig. 1, with the cutters in expanded positions, the showing of the hole and casing being omitted, and the spring-holding means being shown partly introduced to operative position and following a pilot key which precedes such spring-holding means in such introduction;

Fig. 3 is a View similar to Fig. 1, taken at right angles to the line of vision in Fig. 1, the casing and hole illustration being likewise omitted, and the bits or cutters being, in expanded positions; and,

Fig. 4 is a detail transverse sectional view taken upon the line fc4-m4, Fig. 8, and looking in the direction of the appended arrows.

Corresponding parts in all the gures are designated by the same reference characters.

Referring with particularity to the drawing, the improved underreamer is disclosed therein as 'comprising a hollow or bored body A within which is mounted for lengthwise play a bit-carrying rod 5 surrounded by a coil compression spring 6 adjustably confined at its upper end by a nut 7, and confined at its lower end by spring-holding means a applied to the body A. The body of the reamer in the specific construction shown is disclosed as 'terminating a its lower end in spaced prongs o which are provided with terminal extensions 8 having inclined lateral bearing surfaces 8a and more sharply inclined end bearings 6 lwith which the cutters B cooperate in ascending into expanded working positions or descending into contracted or collapsed inoperative positions; the cutters having lateral shoulders 9 which cooperate with such bearing surfaces 8a and end bearings 8b. The bodies of the cutters are suspended adjacent to their upper ends by means of eyes 10 which receive heads 11 projecting oppositely from the lower end of the springactuated rod 5; the upper ends of the cutters, when in expanded positions, engaging with shoulders 12 upon the body for taking the up-thrust of the cutters; and the prongs o having suitable dovetail ways 13 with which dovetails or flanges 13a upon the cutters cooperate to guide the cutters in their movements and receive out-thrust of the cutters. The spring actuated rod 5 at the heads 11 likewise takes in-thrust at the upper ends of the cutters. The holding means a, whereby the lower end of the spring 6 is confined, and the spring, rod 5, and the cutters B are assembled in connection with the body, comprises a key 14 of integral construction, of elongated flat form and having substantially straight sides or edges and, provided at one en d with a tapered nose 14n having a transverse eye 14"; and provided at the other end with a stop or shoulder 14C, which latteris received within a recess or pocket 15 produced in the outer wall of the reamer body A, to the end that the key end 14d having such stop. or shoulder may be driven through a transverse slot 16 in the reamer body, and be entirely contained within the same with the end 14d flush with the wall of the reamer body at one end of such slot. The spring actuated rod 5. is provided with an elongated transverse slot 17 which registers with the slot 16 in the body; and the key 14 is driven with the nose 14a in advance, into and along the slot 16 and through the elongated slot 17' until the shoulder or stop 14c comes to rest in the recess 15., and the nose 14@ comes to rest flush with the opposite wall of the body A. A recess or pocket 18 is formed in the reamer body A at the end of the slot 16 within which is disposed the nose 14a, and a Cotter pin or the like 19 is passed through the eye 14D in the nose 14 and seated in the recess 18. The stop. 14@ prevents the movement of the key 14 in one direction, and the cotter pin prevents the movement of the key in the other direction. The pilot key 2O which is entered in the slots 16 and 17 in advance of the key 14 is wedge shaped, or beveled upon its upper surface, as at 20?, so that it pries. up the spring 6 and makes way for the key 14. The pilot key is first driven in, the key 14 is then entered, and blows or pressure applied to the key force the pilot key on, through and out, and force the key 14 into its final position wherein it may be secured against movement in either direction by the cotter pin 19 and the cooperating shoulder 14'.

The rod 5 may now rise and fall in the collapsing and expanding actions of the cutters, the key retaining the spring always in partially compressed condition, the potential of such compression being increased as the cutters are drawn downward or collapsed. As the rod 5 rises and falls its movement is accommodated with respect tothe relatively immovable keyv by the elongated slot 17, within which the key is positioned. When it is desired to Withdrawl the key so that the rod and its spring and the cutters may be disassembled from the body, as for removing ori replacing the cutters, forl sharpening or substituting fresh cutters, it is only necessary to remove the cotter pin 19, and drive the key out of the slots 16 and 17, with the key end 14d as the advancing end and the nose 14a as the following end. The rod and its spring and cutters may then be drawn downwardly and partially or wholly separated from the body A. It will be noted that the placing of the key in position and its removal from working position are readily and conveniently performed, and that the key is held positively in place independent of the pressure of the spring, and that the key has a snug lit in the body A and the slot 16 therein. Inadvertent breaking of the spring will not cause the key to be loosened and permit it to become displaced, which can only occur if the cotter pin 19 is removed.

It is manifest that many changes may be made in the provision, combination, association, interrelation and formation and construction of parts, members and features without departing from the fair spirit of the invention, all with respect to the specific disclosure of the foregoing description and the drawing.

Having thus disclosed our invention, we claim and desire to secure by Letters Patent:

1. In an underreamer, a body provided with a bore, a bit-carrying rod therein provided with an elongated slot and spring, said body being provided with a transverse slot adapted to register with said other slot, a unitary key adapted to be introduced within said slots when in registration to assemble the bit-carrying rod and spring with the reamer body, and separate means preventing the displacement of said unitary key from said slots in either direction; one of said last named means being carried by the key and the other of said last named means being detachably applied to said key, one at one end of said key and the other at the other end thereof; said reamer body being provided with recesses accommodating said separate last named means one of which is passed through an eye in said key.

2. In an underreamer, the combination with a tubular body having a transverse slot therein, of a slotted bit carrying rod fitted loosely in the tubular body, a coil spring surrounding the rod and operatively connected thereto, a unitary straight sided key extending through the slots of the body and rod and having a working fit in the slots of the body, said key supporting the lower end of the spring and being loosely received within the slot of the rod, and independent fastening means at the ends of the key for holding it removably in position.

3. In an underreamer, the combination with a tubular body having a transverse slot therein and provided with an opening intersecting the slot, of a slotted bit carrying rod fitted loosel in the tubular body, a coil spring surroun ing the rod and operatively connected thereto, a unitary straight sided key extending through the slots of the body and rod and having a working it in the slots of the body, said key supporting the lower end of the spring and being loosely received within the slot of the rod, an opening being provided in the key, and afremovable locking pin extending through the openings of the tubular body and key to hold the key securely in position.

4. In an underreamer, the combination with a tubular body having a transverse slot therein and formed with a recess at one end of the slot and a transverse opening intersecting the opposite end of the slot, of a slotted bit carrying rod fitted loosely in the tubular body, a coil spring surrounding the rod and operatively connected thereto, a unitary straight sided key extending through the slots of the body and rod and having a working fit in the slots of the body, said key supporting the lower end of the spring and being loosely received inthe slot of the rod, one end of the key being formed with a stop shoulder which is received in the before mentioned recess of the body, while the other end of the key is formed with an opening, and a removable locking pin extending through the openings of the body and key to hold the key securely in position.

In testimony whereof, we have signed our names to this specification in the presence of two subscribing witnesses.

ELIHU C. WILSON. WILLIAM W. WILSON.

Witnesses:

ALFRED I-I. DAEHLER, FRANCIS L. IsGRIGG. 

